Varying fluoroelastomer cure across the roller to maximize fuser roller life

ABSTRACT

In accordance with the invention, there are image forming apparatus, fuser members, and methods of making fuser members. The method of making a fuser member can include providing a substrate having a longitudinal axis, providing a first flow coating solution including a fluoroelastomer polymer, and providing a second flow coating solution including a crosslinking agent. The method can also include mixing the first flow coating solution and the second flow coating solution to form a third flow coating solution and forming a continuous fluoroelastomer layer over a surface of the substrate by applying the third flow coating solution onto the substrate in a spiral pattern, wherein the crosslinking agent concentration can be varied along the longitudinal axis by changing the ratio of the first flow coating solution and the second flow coating solution in the third flow coating solution.

RELATED APPLICATION

This application is a division of U.S. patent application Ser. No.12/050,668 filed Mar. 18, 2008, the disclosure of which is incorporatedby reference in its entirety.

FIELD OF THE INVENTION

The present invention relates to image forming apparatus and fusermembers and, more particularly, to methods of making fuser members.

BACKGROUND OF THE INVENTION

In electrostatographic fixing systems, fuser members are coated with anon-adhesive coating including fluoroelastomer polymer to overcome tonerstaining, i.e. the adhesion of the heat softened toner particles ontothe surface of the fuser member. It is well known that the performanceof the fuser members is dependent on the crosslink density of thefluoroelastomer polymer topcoat of the fuser member. Unfortunately,there is no single value of crosslink density that can maximize theperformance of all the key characteristics simultaneously. For instance,it is known that the coating toughness increases if the crosslinkdensity is decreased. This increased toughness improves wearperformance. However, the fluoroelastomer polymer topcoat is moresusceptible to toner staining and contamination at these lower crosslinkdensity levels. Thus, there is a conflict on how to select the nominalcrosslink density of the topcoat.

Accordingly, there is a need to overcome these and other problems ofprior art to provide fuser members with optimized crosslink density andmethods of making them.

SUMMARY OF THE INVENTION

In accordance with various embodiments, there is a fuser memberincluding a substrate having a first edge and a second edge and acontinuous fluoroelastomer layer disposed over a surface of thesubstrate. The continuous fluoroelastomer layer can include a firstregion having a first crosslink density and at least a second regionhaving a second crosslink density, wherein the first region can bedisposed at an interior portion relative to the first and second edgesof the substrate and the at least second region can be disposedproximate to the first region.

According to various embodiments, there is a method of making a fusermember. The method can include providing a substrate having alongitudinal axis, providing a first flow coating solution including afluoroelastomer polymer, and providing a second flow coating solutionincluding a crosslinking agent. The method can also include mixing thefirst flow coating solution and the second flow coating solution to forma third flow coating solution. The method can further include forming acontinuous fluoroelastomer layer over a surface of the substrate byapplying the third flow coating solution onto the substrate from anapplicator in a spiral pattern by rotating the substrate in a horizontalposition about the longitudinal axis and moving the applicator along thelongitudinal axis, wherein the crosslinking agent concentration can bevaried along the longitudinal axis by changing the ratio of the firstflow coating solution and the second flow coating solution in the thirdflow coating solution.

According to another embodiment, there is an image forming apparatusincluding a receptor to receive an electrostatic latent image, at leastone charging component for uniformly charging the receptor, at least oneimaging component to form a latent image on the receptor, and at leastone development component for converting the latent image to a visibleimage on the receptor. The image forming apparatus can also include atransfer component for transferring the visible image onto a media and afuser member for fusing the visible image onto the media. The fusermember can include a substrate having a first edge and a second edge anda continuous fluoroelastomer layer disposed over a surface of thesubstrate, the continuous fluoroelastomer layer including a first regionhaving a first crosslink density and at least a second region having asecond crosslink density, wherein the first region can be disposed at aninterior portion relative to the first and second edges of the substrateand the at least second region can be disposed proximate to the firstregion.

According to yet another embodiment, there is a method of making a fusermember. The method can include providing a substrate having alongitudinal axis, providing a first flow coating solution including afluoroelastomer polymer and a first amount of a crosslinking agent, andproviding a second flow coating solution including the fluoroelastomerpolymer and a second amount of the crosslinking agent. The method canalso include mixing the first flow coating solution and the second flowcoating solution to form a third flow coating solution. The method canfurther include forming a continuous fluoroelastomer layer over asurface of the substrate by applying the third flow coating solutiononto the substrate from an applicator in a spiral pattern by rotatingthe substrate in a horizontal position about the longitudinal axis andmoving the applicator along the longitudinal axis, wherein thecrosslinking agent concentration can be varied along the longitudinalaxis by changing the ratio of the first flow coating solution and thesecond flow coating solution in the third flow coating solution.

Additional advantages of the embodiments will be set forth in part inthe description which follows, and in part will be obvious from thedescription, or may be learned by practice of the invention. Theadvantages will be realized and attained by means of the elements andcombinations particularly pointed out in the appended claims.

It is to be understood that both the foregoing general description andthe following detailed description are exemplary and explanatory onlyand are not restrictive of the invention, as claimed.

The accompanying drawings, which are incorporated in and constitute apart of this specification, illustrate embodiments of the invention andtogether with the description, serve to explain the principles of theinvention.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1A schematically illustrates a cross sectional view of an exemplaryfuser member, according to various embodiments of the present teachings.

FIG. 1B schematically illustrates a top view of the exemplary fusermember shown in FIG. 1A, according to various embodiments of the presentteachings.

FIG. 2 is an end view of a flow coated fuser member being prepared on aturning apparatus, according to various embodiments of the presentteachings.

FIG. 3 is a sectional view of the flow coated fuser member beingprepared on a turning apparatus shown in FIG. 2, according to variousembodiments of the present teachings.

FIG. 4 shows a method of making a fuser member, according to variousembodiments of the present teachings.

FIG. 5 shows a method of making a fuser member, according to variousembodiments of the present teachings.

FIG. 6 shows an exemplary image forming apparatus, according to variousembodiments of the present teachings.

DESCRIPTION OF THE EMBODIMENTS

Reference will now be made in detail to the present embodiments,examples of which are illustrated in the accompanying drawings. Whereverpossible, the same reference numbers will be used throughout thedrawings to refer to the same or like parts.

Notwithstanding that the numerical ranges and parameters setting forththe broad scope of the invention are approximations, the numericalvalues set forth in the specific examples are reported as precisely aspossible. Any numerical value, however, inherently contains certainerrors necessarily resulting from the standard deviation found in theirrespective testing measurements. Moreover, all ranges disclosed hereinare to be understood to encompass any and all sub-ranges subsumedtherein. For example, a range of “less than 10” can include any and allsub-ranges between (and including) the minimum value of zero and themaximum value of 10, that is, any and all sub-ranges having a minimumvalue of equal to or greater than zero and a maximum value of equal toor less than 10, e.g., 1 to 5. In certain cases, the numerical values asstated for the parameter can take on negative values. In this case, theexample value of range stated as “less that 10” can assume negativevalues, e.g. −1, −2, −3, −10, −20, −30, etc.

As used herein, the term “fuser member” is used interchangeably with theterms including fuser rolls, fuser belts, and fuser films.

FIG. 1A schematically illustrates a cross sectional view of an exemplaryfuser member 100, according to various embodiments of the presentteachings. The fuser member 100 can include a substrate 180 having afirst edge 181 and a second edge 182 and a continuous fluoroelastomerlayer 190 disposed over a surface of the substrate 180. In variousembodiments, the continuous fluoroelastomer layer 180 can include afirst region 190 having a first crosslink density and at least a secondregion 192 having a second crosslink density, wherein the first region191 can be disposed at an interior portion relative to the first 181edge and second edge 182 of the substrate 180 and the at least secondregion 192 can be disposed proximate to the first region 191. In someembodiments, the first region 191 can include a stain resistant regionhaving the first crosslink density and the at least second region 192can include one or more wear resistant regions having the secondcrosslink density lower than the first crosslink density. In someembodiments, at least one of the one or more wear resistant regions canbe disposed at a position to reduce wear from edges of a media. In otherembodiments, there can be a gradual increase in the crosslink densitygoing from the second region 192 to the first region 191. In certainembodiments, there can be an abrupt change in the crosslink densitygoing from the second region 192 to the first region 191. Yet, in someother embodiments, there can be one or more regions (not shown) betweenthe first region 191 and the second region 192, wherein each of the oneor more regions (not shown) can have a crosslink density different fromthe first crosslink density and the second crosslink density. In someembodiments, the crosslinking agent to fluoroelastomer polymer ratio canbe from about 0.03 to about 0.04 in the wear resistance region aftercuring. In other embodiments, the crosslinking agent to fluoroelastomerpolymer ratio can from about 0.09 to about 0.1 in the stain resistantregion after curing.

In various embodiments, the continuous fluoroelastomer layer 190 caninclude fluoroelastomer polymer selected from the group consisting ofcopolymers of vinylidene fluoride, hexafluoropropylene, andtetrafluorothylene; and terpolymers of vinylidene fluoride,hexafluoropropylene, and tetrafluorothylene. Other suitable polymers aredescribed in detail in the U.S. Pat. No. 5,945,223, the disclosure ofwhich is incorporated herein in its entirety.

Any suitable material that has satisfactory heat transfercharacteristics can be used as the substrate 180 for the fuser member100. The fuser member 100 can be a roll, belt, flat surface or othersuitable shape used in the fixing of thermoplastic toner images to asuitable media. The fuser member 100 can be a pressure member or arelease agent donor member, preferably in the form of a cylindricalroll, belt, or film. Typically, the roll fuser member can be made of ahollow cylindrical metal core, such as copper, aluminum, steel, orcertain plastic materials chosen to maintain rigidity, structuralintegrity, as well as being capable of having a fluoroelastomer coatedthereon and adhered firmly thereto.

According to various embodiments, there is a method 300 of making afuser member 100, 200 as shown in FIG. 4. In various embodiments, anapparatus 201, schematically illustrated in FIGS. 2 and 3 can be used tomake the fuser member 100, 200. The method 300 can include providing asubstrate 180 having a longitudinal axis 216 as in step 11, providing afirst flow coating solution 202 including a fluoroelastomer polymer asin step 12, providing a second flow coating solution 202′ including acrosslinking agent as in step 13, and mixing the first flow coatingsolution 202 and the second flow coating solution 202′ to form a thirdflow coating solution 202″, as in step 14. In some embodiments, thefirst flow coating solution 202 can include a fluoroelastomer polymerselected from the group consisting of copolymers of vinylidene fluoride,hexafluoropropylene, and tetrafluorothylene; and terpolymers ofvinylidene fluoride, hexafluoropropylene, and tetrafluorothylene. Inother embodiments, the second flow coating solution 202′ can include acrosslinking agent, such as, for example, a bisphenol and a quarternaryphosphonium salt. One of ordinary skill in the art would know that othersuitable fluoroelastomer polymers and crosslinking agents can be used.In various embodiments, other suitable additives including, but notlimited to metal oxides selected from the group consisting of magnesiumoxide, cupric oxide, aluminum oxide, and mixtures thereof can be addedto one or more of the first coating solution 202, the second coatingsolution 202′, and the third coating solution 202″. The method 300 canfurther include step 15 of forming a continuous fluoroelastomer layer190 over a surface of the substrate 180 by applying the third flowcoating solution 202″ onto the substrate 280 from an applicator 212 in aspiral pattern by rotating the substrate 280 in a horizontal positionabout the longitudinal axis 216 and moving the applicator 212 along thelongitudinal axis 212, wherein the crosslinking agent concentration canbe varied along the longitudinal axis 216 by changing the ratio of thefirst flow coating solution 202 and the second flow coating solution202′ in the third flow coating solution 202″. In various embodiments,the step 15 of forming a continuous fluoroelastomer layer 190 over asurface of the substrate 180, 280 can include forming a stain resistanceregion 191 and forming one or more wear resistance regions 192, as shownin FIGS. 1A and 1B. In some embodiments, the method 300 can also includecuring the continuous fluoroelastomer layer 190, such that thecrosslinking agent to fluoroelastomer polymer ratio can be from about0.03 to about 0.04 in the wear resistance region 192 after curing. Inother embodiments, the method 300 can further include curing thecontinuous fluoroelastomer layer 190, such that the crosslinking agentto fluoroelastomer polymer ratio is from about 0.09 to about 0.1 in thestain resistant 191 region after curing.

Referring back to FIG. 2, it shows an end view of a flow coated fusermember 100, 200 being prepared on an apparatus 201. The apparatus 201can be used to apply the third coating solution 202″ to a periphery 204of the fuser member 200. In some embodiments, the third coating solution202″ can be formed in the applicator 212 by mixing the first coatingsolution 202 pumped via pump 206 through a conduit typically in the formof a pipe 210 and the second coating solution 202′ pumped via pump 206′through a conduit typically in the form of a pipe 210′, as shown in FIG.2. In other embodiments, the third coating solution 202″ can be formedin a static mixer (not shown) before being pumped to the applicator 212by mixing the first coating solution 202 and the second coating solution202′ in the static mixer. The applicator 212 can include a nozzle 214through which the third coating solution 202″ can flow onto theperiphery 204 of the fuser member 200.

The third coating solution 202″ can be applied to the periphery 204 in aspiral fashion by rotating the fuser member 200 about its longitudinalaxis 216 in a horizontal position, as shown by the arrow 270 whiletranslating the applicator 212 in a direction 268 parallel to thelongitudinal axis 216 of the fuser member 200 along the length of thesubstrate 280 in a horizontal position, as shown in FIG. 3. As shown inFIG. 3, the applicator 212 can translate from a first position 264 asshown in solid to a second position 266 as shown in phantom. Theapplicator 212 can thus travel along with the slide 234 in the directionof arrow 268. The fuser member 200 can be supported in any suitablefashion such as by feed blocks 272 and can be rotated in any suitablefashion such as by driver 274 which can contact the second end cap 254.Furthermore to provide for the driving of the fuser member 200, thefuser member can have a first end cap 252 located at first end 256 and asecond end cap 254 located at a second end 258.

By accurately controlling the amount of the third coating solution 202″that can be released at the nozzle 214 of the applicator 212,substantially all of the third coating solution 202″ that passes throughthe nozzle 214 can adhere to the fuser member 200. “Substantially all”as used herein means from about 80 to about 100 percent of the coatinginitially released from the nozzle will adhere to the fuser member.Furthermore, by changing the ratio of the amounts of the first coatingsolution 202 and the second coating solution 202′ in the third coatingsolution 202″, one can obtain a desired crosslinking agent concentrationprofile along the longitudinal axis 216.

In various embodiments, using the above described flow coating process,a continuous fluoroelastomer layer 190 having a thickness from about 5μm to about 250 μm with a tolerance of ±2 μm can be formed over thesubstrate 180. However, one of ordinary skill in the art would know thatsubsequent post coating operations, such as, for example, grindingand/or polishing can be required to obtain the preferred dull or flatfinish.

Referring back to FIG. 2, when forming the continuous fluoroelastomerlayer 190 using the apparatus 201 with an applicator 212 through thenozzle 214, the third coating solution 202″ can be applied in athread-like fashion and can have peaks and valleys on the periphery 204of the fuser member 200. In some embodiments, a guide 220 can be placedagainst the periphery 204 of the fuser member 200 as the third coatingsolution 202″ is applied to the fuser member 200 to improve theuniformity of the continuous fluoroelastomer layer 190 over the fusermember 200. U.S. Pat. No. 5,871,832 describes another method, wherein ablade is used at the periphery 204 of the fuser member 200 in order toimprove the uniformity of the coating, and U.S. Pat. No. 5,945,223describes in detail the flow coating process and the apparatus 201, thedisclosures of which are incorporated by reference herein in theirentirety.

The exemplary fuser member 200 shown in the apparatus 201 is a fuserroll. However, the flow coating process described above can be used tomake fuser belts or films. The fuser belts or films can be preferablymounted on a cylindrical mandrill and processed in a manner processsimilar to that heretofore described, with the outer surface of the beltor film being coated.

According to various embodiments, there is a method 400 of making afuser member 100, 200 as shown in FIG. 5. In various embodiments, anapparatus 201, schematically illustrated in FIGS. 2 and 3 can be used tomake the fuser member 100, 200. The method 400 can include providing asubstrate 180 having a longitudinal axis 216 as in step 21 and providinga first flow coating solution 202 including a fluoroelastomer polymerand a first amount of a crosslinking agent as in step 22. The method 400can also include providing a second flow coating solution 202′ includinga fluoroelastomer polymer and a second amount of a crosslinking agent asin step 23 and mixing the first flow coating solution 202 and the secondflow coating solution 202′ to form a third flow coating solution 202″,as in step 24. In various embodiments, other suitable additivesincluding, but not limited to metal oxides selected from the groupconsisting of magnesium oxide, cupric oxide, aluminum oxide, andmixtures thereof can be added to one or more of the first coatingsolution 202, the second coating solution 202′, and the third coatingsolution 202″. The method 400 can further include step 25 of forming acontinuous fluoroelastomer layer 190 over a surface of the substrate 180by applying the third flow coating solution 202″ onto the substrate 280from an applicator 212 in a spiral pattern by rotating the substrate 280in a horizontal position about the longitudinal axis 216 and moving theapplicator 212 along the longitudinal axis 212, wherein the crosslinkingagent concentration can be varied along the longitudinal axis 216 bychanging the ratio of the first flow coating solution 202 and the secondflow coating solution 202′ in the third flow coating solution 202″. Invarious embodiments, the step 25 of forming a continuous fluoroelastomerlayer 190 over a surface of the substrate 180, 280 can include forming astain resistance region 191 and forming one or more wear resistanceregions 192, as shown in FIGS. 1A and 1B. In some embodiments, themethod 400 can also include curing the continuous fluoroelastomer layer190, such that the crosslinking agent to fluoroelastomer polymer ratiocan be from about 0.03 to about 0.04 in the wear resistance region 192after curing. In other embodiments, the method 400 can further includecuring the continuous fluoroelastomer layer 190, such that thecrosslinking agent to fluoroelastomer polymer ratio is from about 0.09to about 0.1 in the stain resistant region 191 after curing.

According to various embodiments, there is an image forming apparatus600 as shown in FIG. 6. The image forming apparatus 600 can include areceptor 62 to receive an electrostatic latent image, at least onecharging component 64 for uniformly charging the receptor 62, and atleast one imaging component 66 to form a latent image on the receptor62. The image forming apparatus 600 can also include at least onedevelopment component 68 for converting the latent image to a visibleimage on the receptor 62 and a transfer component 69 for transferringthe visible image onto a media. The image forming apparatus 600 canfurther include a fuser member 60, 100 as shown in detail FIGS. 1A and1B for fusing the visible image onto the media. The fuser member 100 caninclude a substrate 180 having a first edge 181 and a second edge 182and a continuous fluoroelastomer layer 190 disposed over a surface ofthe substrate 180, the continuous fluoroelastomer layer 190 can includea first region 191 having a first crosslink density and at least asecond region 192 having a second crosslink density, wherein the firstregion 191 can be disposed at an interior portion relative to the first181 and second 182 edges of the substrate 180 and the at least secondregion 192 can be disposed proximate to the first region 191. In variousembodiments, the first region 191 can include a stain resistant regionhaving the first crosslink density and the at least second region 192can include one or more wear resistant regions having the secondcrosslink density lower than the first crosslink density. In someembodiments, at least one of the one or more wear resistant regions canbe disposed at a position to reduce wear from edges of the media.

Examples are set forth hereinbelow and are illustrative of differentamounts and types of reactants and reaction conditions that can beutilized in practicing the disclosure. It will be apparent, however,that the disclosure can be practiced with other amounts and types ofreactants and reaction conditions than those used in the examples, andthe resulting devices various different properties and uses inaccordance with the disclosure above and as pointed out hereinafter.

EXAMPLES Prophetic Example 1 Preparation of First Flow Coating Solutionwithout Curative (Part A)

About 60 grams of VITON GF®, a terpolymer of vinylidene fluoride,hexafluoropropylene and tetrafluoroethylene (DuPont, Wilmington, Del.)and about 197.8 grams of methyl isobutyl ketone are stirred at ambienttemperature of about 25° C. using a Union Process O1 attritor (UnionProcess, Inc., Akron, Ohio) containing about 2,500 grams of about ⅜ inchsteel shots for about 30 minutes to form a polymer solution. Theattritor is externally cooled with a water jacket to maintain thesolution temperature at about 25° C. Without external cooling, thetemperature of the solution in the attritor can rise to about 33° C. Theresultant mixture is then filtered through about ⅛ inch coarse nylonfilter cloth.

Prophetic Example 2 Preparation of Second Flow Coating Solution withCurative (Part B)

A mixture of about 1.2 grams (about 0.407 weight %) of magnesiumhydroxide (Merck and Company, MAGLITE D™), about 0.6 gram (about 0.203weight %) of calcium hydroxide (Baker reagent grade), and about 3.5grams of VITON CURATIVE 50® (DuPont) and about 100 grams of methylisobutyl ketone are stirred at ambient temperature of about 25° C. usinga Union Process O1 attritor containing about 2,500 grams of about ⅜ inchsteel shots for 30 minutes to form a curative solution.

Prophetic Example 3 Fabrication of a Fuser Roll

Mix the first flow coating solution (Part A) of Prophetic example 1 withthe second flow coating solution (Part B) of Prophetic example 2 at theflow coating head to form a third flow coating solution. Apply the thirdflow coating solution onto a metal roll, such that the VITON CURATIVE50® concentration in the coating varies from about 4-5 weight % in thewear resistance region (low cure zone) to about 5-7 weight % in thestain resistant region (high cure zone). The coated metal roll is thenthermally cured for about 4 hours at about 45° C., about 2 hours atabout 75° C., about 16 hours at about 95° C., followed by ramp heatingto about 400° C. for about 16 hours.

Prophetic Example 4 Preparation of First Coating Solution (Part C)

About 60 grams of VITON GF®, a terpolymer of vinylidene fluoride,hexafluoropropylene and tetrafluoroethylene (DuPont) and about 197.8grams of methyl isobutyl ketone are stirred at ambient temperature ofabout 25° C. using a Union Process O1 attritor containing about 2,500grams of about ⅜ inch steel shots for about 30 minutes to form a polymersolution. The attritor is externally cooled with a water jacket tomaintain the solution temperature at about 25° C. Without externalcooling, the temperature of the solution in the attritor can rise toabout 33° C. A mixture of about 1.2 grams (about 0.407 weight %) ofmagnesium hydroxide (Merck and Company, MAGLITE D™), about 0.6 gram(about 0.203 weight %) of calcium hydroxide (Baker reagent grade), andabout 3.5 grams of VITON CURATIVE 50® (DuPont) are added and stirring iscontinued for about 15 more minutes. About 23.62 grams (about 8 weight%) of methanol is then added, and stirring is continued for 15additional minutes. The resultant mixture is then filtered through ⅛inch coarse nylon filter cloth.

Example 5 Preparation of First Coating Solution (Part D)

About 60 grams of VITON GF®, a terpolymer of vinylidene fluoride,hexafluoropropylene and tetrafluoroethylene (DuPont, Wilmington, Del.)and about 197.8 grams of methyl isobutyl ketone are stirred at ambienttemperature of about 25° C. using a Union Process O1 attritor containingabout 2,500 grams of about ⅜ inch steel shots for 30 minutes to form apolymer solution. The attritor is externally cooled with a water jacketto maintain the solution temperature at about 25° C. Without externalcooling, the temperature of the solution in the attritor can rise toabout 33° C. A mixture of about 1.2 grams (about 0.407 weight %) ofmagnesium hydroxide (Merck and Company, MAGLITE D™), about 0.6 gram(about 0.203 weight %) of calcium hydroxide (Baker reagent grade), andabout 2.7 grams of VITON CURATIVE 50® (DuPont) are added and stirring iscontinued for about 15 more minutes. About 23.62 grams (about 8 weight%) of methanol is then added, and stirring is continued for about 15additional minutes. The resultant mixture is then filtered through about⅛ inch coarse nylon filter cloth.

Prophetic Example 6 Fabrication of a Fuser Rolls

Mix the first flow coating solution (Part C) of Prophetic Example 4 withthe second flow coating solution (Part D) of Prophetic Example 5 at theflow coating head to form a third flow coating solution. Apply the thirdflow coating solution onto a metal roll, such that the VITON CURATIVE50® concentration in the coating varies from about 4-5 weight % in thewear resistance region (low cure zone) to about 5-7 weight % in thestain resistant region (high cure zone). The coated metal roll is thenthermally cured for about 4 hours at about 45° C., about 2 hours atabout 75° C., about 16 hours at about 95° C., followed by ramp heatingto about 400° C. for about 16 hours.

While the invention has been illustrated respect to one or moreimplementations, alterations and/or modifications can be made to theillustrated examples without departing from the spirit and scope of theappended claims. In addition, while a particular feature of theinvention may have been disclosed with respect to only one of severalimplementations, such feature may be combined with one or more otherfeatures of the other implementations as may be desired and advantageousfor any given or particular function. Furthermore, to the extent thatthe terms “including”, “includes”, “having”, “has”, “with”, or variantsthereof are used in either the detailed description and the claims, suchterms are intended to be inclusive in a manner similar to the term“comprising.” As used herein, the phrase “one or more of”, for example,A, B, and C means any of the following: either A, B, or C alone; orcombinations of two, such as A and B, B and C, and A and C; orcombinations of three A, B and C.

Other embodiments of the invention will be apparent to those skilled inthe art from consideration of the specification and practice of theinvention disclosed herein. It is intended that the specification andexamples be considered as exemplary only, with a true scope and spiritof the invention being indicated by the following claims.

1. A method of making a fuser member comprising: providing a substrate having a longitudinal axis; providing a first flow coating solution comprising a fluoroelastomer polymer; providing a second flow coating solution comprising a crosslinking agent; mixing the first flow coating solution and the second flow coating solution to form a third flow coating solution; and forming a continuous fluoroelastomer layer over a surface of the substrate by applying the third flow coating solution onto the substrate from an applicator in a spiral pattern by rotating the substrate in a horizontal position about the longitudinal axis and moving the applicator along the longitudinal axis, wherein the crosslinking agent concentration is varied along the longitudinal axis by changing the ratio of the first flow coating solution and the second flow coating solution in the third flow coating solution.
 2. The method of claim 1, wherein the step of providing a first flow coating solution comprising a fluoroelastomer polymer comprises providing a first flow coating solution comprising fluoroelastomer polymer selected from the group consisting of copolymers of vinylidene fluoride, hexafluoropropylene, and tetrafluorothylene; and terpolymers of vinylidene fluoride, hexafluoropropylene, and tetrafluorothylene.
 3. The method of claim 1, wherein the step of providing a second flow coating solution comprising a crosslinking agent comprises providing a second flow coating solution comprising a bisphenol and a quarternary phosphonium salt.
 4. The method of claim 1, wherein the step of forming a continuous fluoroelastomer layer over a surface of the substrate comprises: forming a stain resistance region; and forming one or more wear resistance regions.
 5. The method of claim 4 further comprising mixing the first flow coating solution and the second flow coating solution to form a third flow coating solution such that the crosslinking agent concentration in the stain resistance region is higher than the crosslinking agent concentration in the one or more wear resistance regions.
 6. The method of claim 4 further comprising curing the continuous fluoroelastomer layer, such that the crosslinking agent to fluoroelastomer polymer ratio is from about 0.03 to about 0.04 in the wear resistance region after curing.
 7. The method of claim 4 further comprising curing the continuous fluoroelastomer layer, such that the crosslinking agent to fluoroelastomer polymer ratio is from about 0.09 to about 0.1 in the stain resistant region after curing.
 8. A method of making a fuser member comprising: providing a substrate having a longitudinal axis; providing a first flow coating solution comprising a fluoroelastomer polymer and a first amount of a crosslinking agent; providing a second flow coating solution comprising the fluoroelastomer polymer and a second amount of the crosslinking agent; mixing the first flow coating solution and the second flow coating solution to form a third flow coating solution; and forming a continuous fluoroelastomer layer over a surface of the substrate by applying the third flow coating solution onto the substrate from an applicator in a spiral pattern by rotating the substrate in a horizontal position about the longitudinal axis and moving the applicator along the longitudinal axis, wherein the crosslinking agent concentration is varied along the longitudinal axis by changing the ratio of the first flow coating solution and the second flow coating solution in the third flow coating solution.
 9. The method of claim 8, wherein the step of providing a first flow coating solution comprising a fluoroelastomer polymer comprises providing a first flow coating solution comprising fluoroelastomer polymer selected from the group consisting of copolymers of vinylidene fluoride, hexafluoropropylene, and tetrafluorothylene; and terpolymers of vinylidene fluoride, hexafluoropropylene, and tetrafluorothylene.
 10. The method of claim 8, wherein the step of providing a second flow coating solution comprising a crosslinking agent comprises providing a second flow coating solution comprising a bisphenol and a quarternary phosphonium salt.
 11. The method of claim 8, wherein the step of forming a continuous fluoroelastomer layer over a surface of the substrate comprises: forming a stain resistance region; and forming one or more wear resistance regions.
 12. The method of claim 11 further comprising mixing the first flow coating solution and the second flow coating solution to form a third flow coating solution such that the crosslinking agent concentration in the stain resistance region is higher than the crosslinking agent concentration in the one or more wear resistance regions.
 13. The method of claim 11 further comprising curing the continuous fluoroelastomer layer, such that the crosslinking agent to fluoroelastomer polymer ratio is from about 0.03 to about 0.04 in the wear resistance region after curing.
 14. The method of claim 11 further comprising curing the continuous fluoroelastomer layer, such that the crosslinking agent to fluoroelastomer polymer ratio is from about 0.09 to about 0.1 in the stain resistant region after curing. 